1. Field of the Invention
The present invention relates to a transceiver for optical transmission and a transmission method for the same.
2. Description of the Prior Art
While standardization is being worldwide developed for specifications of products associated with transceivers for optical transmission, higher requirements are particularly proposed for downsizing of the products and lowering in the power source and consumption power. In addition, use of the single power source and removal of the negative power source are highly required due to requirement for general uses in the space or areas to install equipment or the customer environments. To cope with this present state, it is highly required to adopt a booster circuit, leading to a requirement for downsizing and power saving in the transceiver for optical transmission.
To cope with the difficulty, Japanese Patent Laid-Open Pub. No. 2005-80394 describes a power source including a booster circuit to boost a power source voltage to drive a liquid-crystal panel, the booster being also employed as a booster circuit of light-emitting elements. Japanese Patent Laid-Open Pub. No. Hei 4-188686 describes an optical transmitter unit including an intensity modulation section to modulate intensity of light from a light source on the basis of an input signal and a frequency modulation section to modulate a frequency for a power source at a modulation speed sufficiently lower than a modulation speed of the intensity modulation.
Also, according to Japanese Patent Laid-Open Pub. No. Hei 8-191271, there is proposed an optical transmitter including a carrier generator circuit for generating a carrier wave including a predetermined frequency, a mixing circuit for mixing a data signal with a carrier wave to generate a transmission signal, a boosting circuit driven by the carrier wave to produce a boost voltage higher than a power source voltage on the basis thereof, and a light emission section for emitting an optical signal including a quantity of light corresponding to the boost voltage. Additionally, Japanese Patent Laid-Open Pub. No. Hei 10-65627 describes, an optical transmitter unit including a first module for creating an optical signal including a bandwidth indicated by a main signal, a second module for receiving a control signal to expand the bandwidth by modulating the optical signal on the basis of the control signal, a third module operatively connected to an optical transmission line or path and the first module for supplying an optical signal to the optical transmission line and extracting feedback light including a Stimulated Brilluoin Scattering (SBS) light occurring in the optical transmission line, and a fourth module for receiving the feedback light to generate a control signal to set power of the stimulated Brilluoin scattering light to a fixed value.
However, the apparatuses described above are complex and cannot sufficiently suppress noise.